JPH0418886B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a membrane and its manufacturing method. Membranes are thin, flat foils and films characterized by a certain strength and elasticity. They are composed of plastics or natural products and are of great significance in the field of separation technology due to their effectiveness. For example, polymeric membranes are used in industrial separation processes such as desalination by reverse osmosis, dialysis, ultrafiltration, and excess. Excesses are used in particular for the separation of high molecular weight substances from solutions. In particular, microporous membranes and high pressures are used for this purpose. Cellulose acetate membranes are the most widely used,
In addition, polyamides, fluorine-containing polymers,
There is also increasing interest in membranes made of polyureas and sulfonated polyarylethers. Membranes of these materials are anisotropic because they consist of multiple horizontally adjacent layers with different physicochemical properties. For example, they consist of a thick porous support layer and a relatively thin, dense separation layer. All these layers have polymer molecules arranged in the form of a felt. The chain spacing, chain interval distribution, fixed charge density, polarity, and swelling ability of these felt structures determine important properties of the membrane. Thus, for example, in special reverse osmosis membranes, the polymer chains of the separating layer are so dense on average that, despite a good dissolution effect on individual water molecules, the formation of water groups hardly occurs. It is assumed that the separation layer cannot take hydrated ions for the same reason. This is the basis for the high retention power for dissolved salts. Membrane separation methods include layer transitions (e.g. evaporation, distillation)
It has a thermodynamically higher useful effect compared to the separation method by . In addition, there is no problem of heating labor costs. However, there are still considerable unresolved problems in their use on a commercial scale. The throughput of most membranes developed to date is very low. This is due, inter alia, to the excessive thickness of the separating layer. A constant separation layer thickness of 50 Å or less is desirable. This represents a thickness reduction of 5 to 10 times compared to the separation layer thickness commonly used today. Although there are several reports on the thickness of the separation layer on the order of 50 Å, the thickness value in question is generally the minimum thickness of the separation layer, and in all cases there is considerable variation in the thickness. be. This variation is due to the fact that the separating layers are all comprised of polymers with an amorphous, predominantly felt structure that bulges irregularly beneath the support layer. Another reason why the throughput of membranes is so low is that their porous structure undergoes increased compression with increasing pressure differential. The permeability and throughput of amorphous separation layers are concomitantly compromised by the fact that all diffusion coefficients are unnecessarily reduced by indirect factors. The separation performance of HFM developed so far has been inadequate except in special cases. This is due to the felt structure of the separation layer. The lack of high specificity is due to fairly local variations in the spacing between polymer chains in the predominantly amorphous layers. None of the methods applied to the separation layer to date have been able to precisely adjust the average spacing between polymer chains. A separation layer having a substantially constant and precisely adjustable chain spacing is desirable. Membranes developed so far have a very short useful life. This is mainly due to so-called "fouling". It is understood that the fouling is due to the adsorption of mostly negatively charged colloidal impurities and microorganisms on the surface of the separation layer. This drawback is also due in part to the amorphous structure of the separation layer. Fouling is prevented by fixing negative charges on the surface layer of the separation layer. Due to the effect of this fixed charge, the above impurities are electrostatically repelled. This repelling effect increases with increasing fixed charge density. However, the charge density that can be achieved with crosslinked or uncrosslinked amorphous linear polyelectrolytes is lower than the maximum charge density that can be theoretically achieved. A negative charge density substantially corresponding to a very dense fixed charge packing is desired. In a series of special cases, it was believed that membranes could be created that exhibited either high throughput, high resolution, or long useful life. However, it has been impossible to combine these three properties in one and the same film. As mentioned above, the reason for this is mainly due to the amorphous structure of the separation layer. A large number of membranes and their separation layers are described in the literature, in particular in the following fairly recent patent specifications: US Pat. The first reverse osmosis membranes were made of cellulose acetate and were developed by Loeb-Souriranjan.
These are described in US Pat. No. 3,133,132, US Pat. No. 3,133,137 and US Pat. No. 3,344,214. The membrane has two layers,
That is, it is made up of an active layer (separation layer) and a substrate (support layer). Disadvantages of this include the susceptibility of the ester function to hydrolysis, the phenomenon of compaction due to high pressures and the above-mentioned excessive thickness of the separation layer (which largely accounts for the poor throughput of the membrane). Another type of double-layer membrane for reverse osmosis is “Dynamic”
A membrane in which the separation layer closes the opening of the membrane and is formed only at the point of use (US Pat. No. 3,462,362). Originally, this type of membrane could not be made into a ready-to-use form. The nature of the separation layer will depend on the nature of the closure material, and the closure process will need to be repeated relatively frequently. In this case also the separating layer is amorphous, giving rise to the disadvantages mentioned above. Proposals have also been made to increase the number of layers in reverse osmosis membranes (US Pat. No. 3,556,305). Interesting advances can be made in this way. That is, the separation layer has a fairly constant thickness, which significantly improves the dialysis value. This result is achieved by attaching an anisotropic separation layer consisting of a microporous skin and a macroporous matrix to the diffusion membrane (supporting layer) via an adhesive layer. Therefore, the membrane has a four-layer structure. These four layers are - individually speaking - an amorphous felt structure. Other composite membranes are described in US Pat. No. 3,648,845. In this case, a fairly dense separating layer (mainly cellulose acetate) is applied to a porous support (supporting layer) via a surface layer. For that reason,
The surface layer or cover layer mainly prevents the polymer constituting the support layer from penetrating into the support layer. Although separation layers of relatively constant minimum thickness can be created in this manner, other drawbacks due to the amorphous structure still exist. Subsequently, attempts were made to simplify the membrane structure by omitting the surface layer (US Pat. No. 3,676,203). This attempt has proven successful in very specific cases. This was possible by applying a separate layer of polyacrylic acid to a support layer of a cellulose acetate/cellulose nitrate mixture. However, this membrane has disadvantages not only due to the susceptibility of the ester bonds to hydrolysis and the water solubility and swelling properties of the separating layer, but also the well-known disadvantages due to its amorphous structure. German Published Application No. 2557355 discloses a two-layer membrane which, in addition to other favorable properties, has a minimum separating layer thickness and is therefore capable of good reverse osmosis even at moderate pressures. It is said to be a thing. However, given the chemical composition of the membrane and the process by which the separating layer is applied, it is concluded that the two layers of the membrane are amorphous. In addition, the performance of the membrane is not optimal as can be seen from the disclosed figures. A method for producing reproducibly thin polymer films is described in DE 24 20 846 A1. The film-forming material is a linear polymer (eg, a silicone/polycarbonate copolymer). This is dissolved in a readily volatile solvent (eg chloroform) and poured onto the surface of a liquid in which neither the solvent nor the polymer dissolves. Water is preferably used for this purpose. The solution spreads over the surface and the solvent evaporates, leaving a film in the form of a 250 Å to 500 Å thick layer. To reduce the holes in the film thus formed, it is recommended to pour several layers repeatedly. The final film can be coated onto a porous support (for example a permembrane), with which it forms a practical membrane that can be used for separation purposes. Again, the actual separating layer is amorphous, with its disadvantages. In the past, therefore, there was no departure from the concept of an amorphous separation layer with a felt structure for the purpose. Hitherto, there has been no separating layer for this purpose that combines high permeability with high separating power and long service life. It is therefore an object of the invention to provide a membrane which combines a long service life with high permeability, is easy to manufacture and does not have the disadvantages of known membranes. The above objectives can be achieved by creating a separation layer based on the same physicochemical principles found in lipoidal films of biofilms. This lipoid film has a well-aligned velvet structure in contrast to the amorphous felt structure of the separation layer of known practical membranes. The film exhibits high permeability to water, high retention capacity for most salts, clear permeability to low-molecular substances, and is especially very thin.
Its thickness is 1/10 or less of the thickness of a known separation layer.
The thickness is 20 Å to 40 Å, which corresponds to the separation layer thickness desired for practical membranes with high throughput. Due to the orientation of the lipoid molecules, the lipoid film has a palisade or velvet structure, with the long axes of the alkyl chains perpendicular to the membrane plane and thus parallel to the direction of diffusion. Indirect factors are virtually negligible. The film's high permeability to water and high ability to retain substances such as salts are due to the fact that the alkyl chain of the lipoid has a group with a plasticizing function (double bond, side chain methyl group, cyclopropyl group). These groups prevent the lipoid molecules from crystallizing and keep the film in a two-dimensional liquid state. The packing density of the lipoid molecules in these liquid films is on the one hand coarse enough to allow individual water molecules to pass through, but on the other hand so dense as to prevent the formation of water clusters, such as in an amorphous separation layer of a felt-like structure. However, in contrast to the felt structure, the spacing between individual lipoid molecules is very finely divided and the spacing distribution is narrow. By introducing appropriate side chains or functional groups into the main chain, the spacing between lipoid molecules can be maintained accurately.
As a result, the separation power of lipoid films becomes very significant. In addition, the lipoid film in question "self-healed" small wounds because the molecules' fatty chains were mostly occupied by hydrophobic bonds. It is also noted that the lipoid layer of biofilms is optically active. However, the permeability of a biofilm is determined not only by the permeability of its bimolecular lipoid regions, but also by the fact that these lipoid regions can dissolve or absorb hydrophobic carriers or pore molecules. do not have. It is often these carriers or pores that can facilitate highly selective and rapid diffusion of small molecules from one membrane surface to another. It is known from fairly recent research that artificial monomolecular and bimolecular films are suitable as carriers or matrices for the introduction of molecules with selectively permeable channels therein. This pore molecule determines, to a large extent, the permeation behavior of the entire film. According to studies of lipoid monolayers on water surfaces,
Under relatively high pressures per unit area, the lateral spacing between the terminally fixed charges is said to substantially correspond to the theoretical minimum spacing for very dense two-dimensional packing. This distance can be continuously adjusted within certain limits by varying the pressure per unit area. However, the physicochemical construction principles embodied in biolipoid films cannot be applied without restriction or modification to separation layers in practical membranes for a number of reasons. This is because most lipoid films in biological membranes have a so-called "bimolecular" structure. The structure in question is a reversible aggregate of lipoid molecules, each of which has one water-soluble head group and one water-insoluble hydrocarbon group. In principle, the aggregates have exactly the same structure as platelet-like micelles in fairly concentrated aqueous solutions of surfactants. Generally, biological lipoid films are conditioned in a medium with average PH value and moderate temperature. For this reason, the chemical stability of lipoids does not meet particularly stringent requirements. When applying the physicochemical construction principles of biofilm lipoid films to the separation layer of practical membranes, the following drawbacks of lipoid films must be considered: (1) Essentially, bimolecular lipoid films are Hydrophobic, held together by electrostatic bonds, and constituted solely by those bonds. For this reason, these films are essentially soluble in water and their useful life is unsuitable for practical purposes.
In addition, lipoid films are particularly unstable in surfactant-containing aqueous solutions because the lipoid molecules are solubilized in the surfactant micelles. In addition, in practical operations, surfactants are often unavoidable. (2) The fixation of other components of biological bimolecular lipoid films to biological membranes is mostly electrostatic or hydrophobic. Major bonds are relatively rare. Similarly fixing a lipoid film as a separation layer to a practical gel or support layer does not provide a product with a useful life that is adequate in practice. (3) The charged head groups of biological lipoids are generally sensitive to hydrolysis (choline phosphate, ethanolamine phosphate, etc.);
On the other hand, the surface charge density of biological lipoid film is PH
is related to. Both of these properties make it difficult to use biolipoid films as separation layers in practical membranes. Sensitivity to hydrolysis shortens useful life and electrostatic protection against fouling
It can only be achieved within a certain PH range. Surprisingly, the instability of this biolipoid film, which hinders its use as a separation layer in practical membranes, can be reduced by the main physicochemical properties of the film that remain unaffected as follows. . (1) Instead of making bimolecular films from monofunctional lipoid molecules, monomolecular films are made from bifunctional or polyfunctional lipoids or surfactants. Recently, membranes of highly specialized microorganisms [Thermoplasma acidophilum, Sulfolobus acidophilum],
acidocaldarius)], a modified architectural principle has been observed, including a very low
PH values and high temperatures are used, so that the membrane is particularly resistant to hydrolysis. (2) Among the various methods that can be used to coat the porous support layer of the monomolecular separation layer in stable form, two are exemplified: Firstly, mono- or di-functional lipoids or surfactants can be polymerized with each other in the separating layer by means of reactive groups (e.g. double bonds) and with the support layer via other functional groups, and if possible. They can be bonded by interposing a gel layer between them. In this case, the loss of self-healing power is fundamental, since this crosslinking method limits the free instability of the hydrophobic lipoid chains. However, this drawback can be partially overcome by using lipoids or surfactants with two hydrophobic chains, only one of which is a polymerizable group and the other acts as an intramolecular plasticizer. Can be removed. Another possibility is to use lipoids or surface-active molecules whose hydrophilic end groups consist of relatively long reactive chains that penetrate relatively deeply into the gel layer or support layer. These chains serve to crosslink the separating layer molecules and anchor the separating layer to the gel layer or support layer. Therefore, in this process,
No crosslinking takes place in the hydrophobic parts of the separating layer, thus preserving the self-healing power of the separating layer. (3) To avoid the sensitivity of the head group to hydrolysis and obtain a surface charge density that is not affected by pH,
The lipoid or surfactant molecules of the separation layer should contain as charge head groups, preferably sulfonic or phosphonic acid groups. These groups are only slightly sensitive to hydrolysis and are dissociated even in acidic solutions. However, the need to provide a separation layer surface (or rather the ends of lipoids or surfactant molecules remote from the support layer) with a fixed charge only arises when the membrane is used in an aqueous medium, for example for desalination. . In other cases, when the membrane is used in an organic medium, there is no need for a fixed surface charge to be present. In such cases, the hydrolytic sensitivity of biolipoids is not a disadvantage. Therefore, if the membrane is to be used for separations in organic media, the separating layer may have the structure of a half-bimolecular lipoid membrane, and may contain suitable biological lipoids or surfactants of similar structure. It can also be made directly from. Therefore,
The separation layer then consists of a monomolecular lipoid or a surfactant film, with its hydrophobic end facing the organic phase to be separated. It is clear that optically active surfactants or surfactant-like lipoids can also be used for the production of monomolecular separation layers. The chiral surface of a monomolecular separated layer is
Final modification of the surface-active molecules (after the actual separation membrane has been made) can be made by reacting them with, for example, optically active sultones or amino acid derivatives. Finally, monomolecular separation layers can also be used to solubilize or introduce hydrophobic carriers or pore molecules when technically attempting to take advantage of the high transport selectivity of molecules. A well-known example of a hydrophobic K ⁺ selective carrier is valinomycin, while an example of a hydrophobic protein molecule with a K ⁺ selective pathway is gramicidino. In this invention, the separation layer is composed of molecules of a crosslinked monomolecular film, and (a) at least one molecule of the separation layer is in an uncrosslinked state.
(b) The hydrophobic chains of the cross-linked molecules are mainly arranged perpendicular to the membrane surface and parallel to the diffusion direction. (c) the molecules of the separation layer are cross-linked to each other via a functional group in at least one hydrophobic chain thereof and/or via a functional group in at least one hydrophilic group thereof; The invention relates to an excess membrane comprising a separation layer and a support layer. The overeffect of the separation layer of this invention is expressed as follows. That is, for example, when a monomolecular layer of a surfactant is deployed at the boundary between the aqueous phase and the air, the head group of the molecule will be located in the aqueous phase and the water-insoluble chain of the molecule will be located in the air. Here, the unfolded molecules are pressed against each other on the surface of the aqueous phase and are closely located laterally, and the molecular chains stand upright on the surface of the aqueous phase. In this state, the surfactant molecules are cross-linked to each other, resulting in a substantially uniform two-dimensional structure (the length of the molecular chain is negligible with respect to the extent of the surface of the aqueous phase). Here, since each surfactant molecule is arranged horizontally in an orderly manner, the spaces between these molecules also exist in an orderly arrangement. The space between these holes becomes the pores of the separation layer for filtration.
All molecules smaller than the distance between the surfactants will pass through this pore, and all larger molecules will be returned. The separation layer of the invention thus acts as a membrane. In the simplest case, the method according to the invention uses surfactants or surfactant-like lipoids with a strongly hydrophilic head and a hydrophobic end. However, surfactants or surfactant-like lipoids are also used, which are characterized by having a long hydrophobic central part, with strongly hydrophilic groups at one end and weakly hydrophilic groups at the opposite end. It is possible. (1) The hydrophilicity of the strongly hydrophilic group at one end and the hydrophobicity of the hydrophobic tail or hydrophobic center at the other end make it possible for the surfactant molecule as a whole to remain on the surface of an aqueous solution even though it is not very soluble in water. , or at the interface between an aqueous solution and an organic liquid immiscible therewith, with weakly hydrophilic groups facing the gas zone or organic liquid, mutually aligned to effectively spread perpendicular to the membrane plane. (2) The hydrophobic tail or hydrophobic center contains a polymerizable group and thus has the opportunity to crosslink with the hydrophobic center of at least two adjacent molecules, and/or the highly hydrophilic group is polymerizable and/or with highly hydrophilic groups of at least two adjacent surfactant molecules;
and the possibility of crosslinking with other molecules dissolved in the aqueous phase which, after crosslinking with the surfactant molecules and with each other, constitute the gel layer or support layer of the membrane. (3) Weakly hydrophilic groups combine with stronger hydrophilic groups, or
It may also be converted into a stronger hydrophilic group than itself. That is, weakly hydrophilic groups include sultonic acid groups, phosphonic acid groups, sulfuric acid groups, phosphoric acid groups, amino acid groups, carboxylic acid groups, primary, secondary, or tertiary amine groups, quaternary ammonium groups, or other strongly hydrophilic groups. sulfonic acid group, phosphonic acid group, sulfuric acid group, phosphoric acid group,
It can be converted into an amino acid group, a carboxylic acid group, or a primary, secondary or tertiary amine group, a quaternary ammonium group, other positively charged groups or other strongly hydrophilic groups. As mentioned above, it is a surfactant or surfactant-like lipoid whose hydrophobic tail or hydrophobic center consists of straight or branched hydrocarbon chains and/or partially or fully halogenated straight or branched hydrocarbon chains. Preference is given to using those consisting of hydrocarbon chains or straight or branched silicon chains. Other preferred surfactants or surfactant-like lipoids include at least one sulfonic acid on at least one hydrophobic chain or in the vicinity of a strongly hydrophilic group at their end facing the gel layer or support layer. group, phosphonic acid group, sulfate group, phosphoric acid group,
Some are distinguished by the inclusion of carboxylic acid groups, other groups which are negatively charged in the dissociated state, primary, secondary or tertiary amino groups, quaternary ammonium groups or other positively charged groups. Other preferred surfactants or surfactant-like lipoids include hydrocarbon-based parent substances such as tri-,
Tetra and higher terpenes, especially carotenoids. Furthermore, surfactants or surfactant-like lipoids containing a diene group or diacetylene group as a polymerizable function at the hydrophobic tail or the hydrophobic center are preferred. Other suitable surfactants or surfactant-like lipoids include mono-,
Residues of di-, tri- or higher saccharides, onic acids, sugar acids or amino sugars, residues of amino acids or oligopeptides, residues of polyhydric alcohols, aldehydes, carboxylic acids, or amines, Some carboxylic acid esters, epoxies,
Included are those distinguished by groups containing episulfide or sulfhydryl functional groups, groups containing activated double bonds (eg vinyl sultones), or groups containing masked isocyanates (eg carboxylic acid acids). The invention also provides that (a) a surfactant or surfactant-like lipoid molecule is placed under a spreading pressure or maintained at an average spacing on the surface of an aqueous solution or in a region immiscible with the aqueous solution; (b) crosslinking the surfactant or surfactant-like lipoid molecules with each other; and (c) coating the thus crosslinked separation layer on a support layer or gel layer. The present invention relates to a method for producing an excess membrane, characterized in that steps (b) and (c) are carried out continuously, but in an arbitrary order. According to this invention, (1) surfactant molecules or surfactant-like lipoid molecules are spread out at a certain average spacing on the surface or interface of an aqueous solution; (2) the spread surfactant molecules or The surfactant-like lipoid molecules are cross-linked to each other at either the hydrophobic or hydrophilic portions of the monomolecular film; (3) optionally, the surfactant molecules or the weakly hydrophilic ends of the surfactant-like lipoid molecules are , sulfonic acid group,
Phosphonate group, sulfate group, phosphate group, amino acid group,
carboxylic acid group, primary, secondary or tertiary amino group,
Convert into a quaternary ammonium group, other positively charged group or other strongly hydrophilic group, or convert into a sulfonic acid group, phosphonic acid group, sulfuric acid group, phosphoric acid group, amino acid group, carboxylic acid group, primary, secondary or containing either a tertiary amine group, a quaternary ammonium group, another positively charged group, or a group in an open or masked form (the masked hydrophilic group is then released) with another hydrophilic group. A method is provided for producing an overmembrane comprising the steps of: (4) coating a cross-linked separation layer on a porous, mechanically stable support layer; The order of the steps described above is not absolutely essential. For example, surfactant molecules may be coated onto the support layer prior to crosslinking. The particular order to be chosen in each case will depend in particular on the stability of the diffused monomolecular film. In the case of unstable monomolecular films, the subsequent hydrophilization of the weakly hydrophilic ends of the surface-active molecules should only be carried out after the separation layer has been applied to the support layer. Additionally, the separation layer need not be coated directly onto the support layer. Alternatively, a porous gel layer can be interposed, for example if the surface of the support layer is very rough. A porous gel may be introduced into the pores of the support layer when the pores of the support layer are large enough that the monomolecular support layer cannot compensate for the porosity without additional mechanical support. It is advisable to do this, for example, if it is desired that the excess membrane function at very high pressures. In a preferred case, it is sufficient to simply place the separation layer on top of the support layer. This is the case when the supermembrane is used in a hydrophobic medium. In other cases, it is necessary to crosslink the separation layer/support (gel) layer in order to prevent the separation layer from peeling off again. This is recommended, for example, when the overmembrane is used with aqueous surfactant-containing solutions. The separation layer can be applied to the support layer in different ways. The choice of a particular method will primarily depend on whether a small or large membrane surface is to be produced. For small membrane surfaces, it is best to use the Langmiur or Blodget methods. In these methods, a monomolecular film is compressed to a predetermined spreading pressure with a barrier on the surface of the subphase. Only initially the film is crosslinked. The simplest way to apply a porous support layer is to place the porous support membrane just below the water surface at a slight angle or flat and then lower the liquid level. The crosslinked monomolecular film itself is coated on the support layer, and the water present is allowed to flow out from between the film and the support layer, or is suctioned away from the support layer to evaporate or flow out, so that the film completely covers the entire surface of the support layer. become. Both layers adhere relatively firmly to each other. At this point, both layers will be crosslinked to each other. Furthermore, as a final step, the surface of the separation layer may be further made hydrophilic. The order of the individual steps can also be carried out differently. The monomolecular film is first applied to the support layer and then crosslinked by itself or together with the support layer. A less precise but simpler method of coating the separating layer on the support layer, which can be used to produce large surface area membranes, dispenses with a barrier for regulating certain spreading pressures. Instead, a high quality surfactant is spread onto the surface of the solution in a trough with a funnel-shaped top and hydrophobic walls (eg PTFE). In this case, the drop in liquid level causes compression of the monomolecular film to a given area. The measurement of the amount of surfactant to be coated must be accurate so that the area falls exactly where the upper funnel ends and the lower cylinder or column begins of the trough. Further reductions do not result in further compression of the film. The actual application of the separation layer to the support layer and the crosslinking reaction are carried out in the same manner as described above. In a third method, the support layer is extracted from below the aqueous subphase and through a monomolecular film under constant spreading pressure. In this case, water also flows between the film and the support layer. In a fourth possible method, a support layer is introduced onto the monomolecular (crosslinked or uncrosslinked) surfactant from above at a slight angle, compressing the layer below the next surface. Of course, it is best to use a hydrophobic support layer for this purpose. In addition, there is a fifth method that can be employed when the surfactant is still clearly soluble in non-polar organic solvents. In this case, the surfactant and/or protective layer should contain reactive groups and should be able to react with each other without the addition of crosslinking reagents.
The surfactant is dissolved in the organic phase and the hydrophilic support membrane (optionally wet) is simply dipped into and removed from the resulting solution. The surfactant and the support layer surface then react with each other to form a monomolecular surface film. Surfactants are selected which are capable of crosslinking themselves even in the presence of water. In this case a crosslinked separation layer is obtained. The remaining operations are performed according to the requirements as previously described. This method can be used when the pores of the support layer are not too large or are closed with a pore gel, or when the entire support layer is coated with a gel layer. It will also be clear that one of the five methods described above may be modified into a continuous or semi-continuous method for coating the support layer in the form of an endless strip. Mechanically stable porous materials can be used as porous support layers in nature. The choice of the support layer depends, first of all, on whether or how it is to be crosslinked with the separation layer and what requirements of its chemical, mechanical and thermal stability are to be met. The membrane according to the invention has all the characteristics that make the high resolution desirable dynamic properties of lipoidal films of biofilms, and in addition has a high resistance to fouling. For these reasons, the membrane of this invention is suitable for desalination,
It is suitable for use in a variety of practical separation methods including spill treatment, in some respects petroleum refining and separation of optical isomers. Desalination by reverse osmosis (excess) of seawater has advantages from an energy standpoint compared to commonly used distillation methods. Membrane processes are isothermal and instead of high vaporization enthalpies, there is a small amount of osmotic work in the form of pump energy. In the past, the advantages of this membrane method over distillation methods, as well as the drawbacks of inadequate throughput and short useful life, hindered and greatly delayed the use of membrane methods for seawater desalination on a large scale. Ta. However, compared to membranes previously used for seawater desalination, the membrane of the present invention has significantly higher throughput and improved useful life.
Therefore, it opens the way to a large-scale membrane method for obtaining pure water from seawater. Effluent treatment is the area of application where the high electrical surface charge density separating layer of the supermembrane of this invention with additional hydrophilic properties represents the most value. The reason is that in this field relatively weakly charged or completely uncharged surfaces have a great effect on the lifetime of the membrane. Pervaporation of liquid through a membrane
The separation of organic liquid mixtures, especially of hydrocarbon groups (C ₈ -mixtures), has rarely gone beyond the experimental stage.
This evaporation method is also a permeation method and relies on phase transitions just like the distillation method. For this reason, evaporation methods use approximately the same amount of energy as distillation methods. Also, the throughput of the evaporation method is lower than that of the distillation method. However, theoretically, the evaporation method can exhibit a very high degree of selectivity, and the lack of selectivity has been the primary obstacle to practical application of the evaporation method so far. The membrane according to the invention has a high selectivity, which is essential for the practical application of evaporation methods. The membrane for the evaporation method is
It is not necessary to have a monomolecularly separated layer of bifunctional surfactant. The reason is that contamination is not an important factor in this case and the separation layer does not require a surface negative charge. Therefore, evaporative films can also be made from monofunctional surfactants,
Therefore, such a membrane can be said to be the simplest form of membrane in question here. The process of separating optical isomers by filtration through a chiral separating layer is characterized by a particularly high selectivity due to the essentially two-dimensional crystalline nature of the tightly packed separating layer, and in addition, the same selection This method has a considerably higher throughput than its corresponding method, especially the crystallization method. Additionally, it is not a difficult method. Since a relatively small amount of surfactant is required to create the separation layer, it is possible to prepare the separation layer from an optically active surfactant and/or to create an initially optically inactive surfactant that is later chiralized to the ω-position. None of the things you do are particularly expensive. The separating layer of the membrane according to the invention is generally 20-60 Å,
Preferably the thickness is 20-50 Å, most preferably 20-40 Å. If desired, this separating layer may be significantly thinner. However, it is a particular advantage of the membrane of the invention that the separation layer is sufficiently strong with a thickness of 50 Å and thus exhibits good separation performance. The support layer is 0.05mm to 1.0mm thick, preferably 0.1mm
It is the thickness, and may be thinner or thicker depending on necessity. The membrane according to the present invention, as well as "separation layer with felt structure", "separation layer with velvet structure", "bimolecular film", "monomolecular film", "support layer", "gel layer", "monolayer Terms such as "functional lipoid", difunctional and polyfunctional lipoid" are explained with reference to the accompanying FIGS. 1-11. FIG. 1 shows a cross-section of a conventional membrane, in which a felt-structured separation layer 1 is coated with a coarse-porous support layer 2. FIG. 2 shows a cross-section of the membrane of the invention, in which a separating layer 3 having a velvety structure is coated on a coarse-porous support layer 2. FIG. FIG. 3 is a cross-section of another membrane of the invention, in which a separating layer 3 having a velvety structure is coated with a finely porous gel layer 4, which is coated with a coarsely porous support layer 2. FIG. 4 is a cross-sectional view of a monofunctional lipoid or a bimolecular film of a surfactant, in which the functional groups (circled) are hydrophilic groups. Figures 5 to 8 are cross-sectional views of monomolecular films. FIG. 5 shows a monofunctional lipoid or a monomolecular film of a surfactant, and the functional groups (circled) are hydrophilic groups. FIG. 6 shows a bifunctional lipoid or a monomolecular film of a surfactant, and the functional groups (circled) are functional groups. Figure 7 shows a monomolecular film of trifunctional lipoid or surfactant, in which two identical functional groups (circled parts) are hydrophilic, and the third functional group (tail part) is another hydrophilic residue. . Figure 8 shows a crosslinked monomolecular film of trifunctional lipoid or surfactant, in which two identical functional groups (circled) are hydrophilic groups, and a third functional group is used for crosslinking at the hydrophobic part of the film. There is. Figures 9-11 are cross-sectional views of the separation layer of the invention to which the support layer is fixed. FIG. 9 shows a crosslinked monomolecular film of trifunctional lipoids or surfactants. Two functional groups (circles) are hydrophilic groups, and the third functional group (in this case another hydrophilic group) is used for crosslinking with the hydrophilic groups of the film. FIG. 10 shows a crosslinked monomolecular film of a trifunctional lipoid or surfactant, where two identical functional groups (circles) are hydrophilic groups and the third group is another hydrophilic group. Crosslinking is a subphase (gel or support layer)
This is done in macromolecules. FIG. 11 shows a crosslinked monomolecular film of bifunctional lipoids or surfactants. The molecule has a fixed charge (circle) and other hydrophilic groups through which it is crosslinked with the macromolecules of the subphase (gel or support layer). The hydrophobic groups of this lipoid or surfactant are exposed at the surface of the separation layer. From the following observations, what has been made regarding surfactants applies to the surfactants used in the preparation of the separation layer as well as to the surfactants contained in the separation layer. The term "surfactant" used next includes surfactant-like lipoids. “Surfactant” is
Since lipoids are fat-like substances, they are generally understood to be surface-active compounds. Surfactant-like lipoids are therefore surface-active, fat-like substances. The introduction of a gel layer between the separation layer and the support layer is necessary in the following cases: That is, when the pore diameters of the support layer cannot be connected by a crosslinked separation layer, or when the crosslinked separation layer is not mechanically stable enough on its own. The gel layer may be of the same material as the support layer, provided that its pore diameter is sufficiently small. In the following description, the gel layer of the membrane is not depicted separately from the support layer, but forms part of the support layer. Although the literature describes lipoids containing a hydrophobic center and two different hydrophilic end groups, the stronger hydrophilic end groups crosslinking with at least two corresponding groups of the same molecule, but for practical purposes it is difficult to use (Biochimica et Biophysica Acta,
360 (1974) 217–229, 487 (1977) 37–50). The hydrophobic center may be a straight-chain or branched aliphatic group, such as a straight-chain or branched alkyl, alkenyl, alkynyl group. Some or all of the hydrogen atoms in the aliphatic group of the hydrophobic center may be substituted with fluorine atoms or halogen atoms. In addition, the chain of the hydrophobic center may be interrupted with an oxygen atom. The hydrophobic central portion may include one or more double bonds and triple bonds. If they contain several double or triple bonds, they are preferably conjugated. In addition, the hydrophobic center may contain double and triple bonds at the same time. The hydrophobic center may also contain a mixed aliphatic and aromatic group. Even if the hydrophobic center contains such a mixed group, the above definition as an aliphatic part applies. The aromatic group in the hydrophobic center can be formed by something like a phenylene group or a naphthalene group. The hydrophobic center may be composed of two parallel aliphatic chains, parallel aromatic chains or aromatic/aliphatic chains. These chains may be interconnected. Next, an example of the hydrophobic center is shown. The hydrophobic center is, for example, a linear aliphatic group (a), (f), (g), a branched aliphatic group (b), (c), or an aromatic/aliphatic group. It may also be two parallel chains (d), (e), (g) connected to each other at the ends. (a) X-(CH ₂ ) _o -Y (n=12-44) (b) X-[CH ₂ -CH(CH ₃ )-CH ₂ -CH ₂ ] _o -Y
(n=4-12) (f) X-(CH ₂ ) _o -C≡C-C≡C-(CH ₂ ) _o -Y
(n=6-22) In the above examples (a) to (g), Y represents a strong hydrophilic group and X represents a weak hydrophilic group. It is a surfactant that is crosslinked with Examples (f) and (g) are surfactants that crosslink at the hydrophobic central functional group. In these cases, the bonding with the support layer takes place through the strongly hydrophilic group Y. In example (g), the surfactant is used as the second plasticizing agent.
Contains hydrocarbons. Example (e) is a hydrocarbon skeleton similar to the membrane lipoids of Thermoplasma acidophilum. The number of carbon atoms in the hydrophobic center is balanced with the number of carbon atoms in the biofilm lipoid. The hydrophobic end of biological lipoids contains approximately 12-22 carbon atoms. Therefore, the thickness of the bimolecular lipoid film is
Approximately corresponds to 24 to 44 carbon atoms. Therefore,
The hydrophobic center of the surfactants according to the invention (if formed of hydrocarbon groups) contains up to 44 carbon atoms, preferably up to 36 carbon atoms. If the hydrophobic center is formed from partially fluorinated hydrocarbons or completely fluorinated carbon, the number of carbon atoms can be considerably lower. Examples (a)-(g) do not represent a complete list. In formulas (a) to (g), the hydrogen atoms of the aliphatic groups may be completely or partially substituted with fluorine atoms. In formulas (a) and (d), n is 12 to 44, preferably 18 to 40,
More preferably 24-36. In formula (g), m has the same meaning as n in formulas (a) and (d). In formula (b), n is 4-12, preferably 6-10, more preferably 7-9. In formula (c), n is 3 to 14, preferably 6 to 12, more preferably 9 or 10. In formula (e), n is 4 to 10, preferably 7 to 9, and more preferably 8. In formula (f), n is 6-22, preferably 8-18, more preferably 10-16. Examples of the strong hydrophilic group Y of the surfactant include the following. Residues of mono-, di-, or higher oligosaccharides (e.g., hexoses, heptuloses, octrose, and residues of sutucharose, lactose, maltose, and raffinose),
Mono-, di-, Tri- or oligopeptide residues (eg, polyserine, polylysine, polyhydroxyproline, polyornithine residues, etc.). Alternatively, the residues may be residues of sugar molecules bonded to each other via an ether bridge. Other possibilities include short chain condensates of epichlorohydrin and glycidol. The above list should not be construed as exhaustive. having at its disposal so many reactive groups that the strongly hydrophilic group can be crosslinked simultaneously with at least two surfactant molecules adjacent thereto, and optionally with the polymer molecules of the subphase; This is an important factor. Examples of weakly hydrophilic groups X in surfactants include -OH, _-NH2 , -SH, -CHO, _-COCH3 , -CH
=CH−COOR, −CH=CH ₂ , [Formula] −CN, −CON ₃ , −COOR, −SR, −S−SR, −
Examples include SCN or halogen atoms (chloro, brome, iodo). This is also not a complete restoration. Under special conditions, the -COO group is also suitable for use as a weakly hydrophilic group. An important factor is that the weakly hydrophilic group has a fixed negative charge or can be converted into another hydrophilic group, or can be extended to a fixed negative charge or other hydrophilic group-containing group. The basis of the problem is
Preferably it is an anion of sulfonic acid. The term "not appreciably soluble in water" means that the surfactant molecules applied to the surface of the aqueous phase remain on the surface and do not dissolve in the aqueous phase to any "appreciable" extent. means. The solubility in the aqueous phase is preferably less than 10 ^-6 mol/, preferably
It should be 10 ^-8 mol/. When a monomolecular surfactant layer is formed at the interface between aqueous and organic phases, its solubility in the organic phase should also be as low as possible. The term "spreading" is a specialized term in surface chemistry that is familiar to those skilled in the art. This means that the molecules on which the surface can move completely occupy the surface for their movement, just as a gas molecule takes up all the volume in which it can move. Formally, molecules spread out on a surface behave like two-dimensional gases. The average spacing between spread molecules can be deduced from the number of molecules per cm ² of surface area. This interval is also
It can be measured from the surface area available for a certain number of molecules to span. Spreading need not necessarily take place at the interface between liquid and gas phases, but may also take place at the interface of two immiscible liquids, for example water and petroleum. From spreading experiments, the minimum surface area required for relatively long linear fatty acids or hydrocarbons placed perpendicular to the water surface is approximately 25 Å ² . Therefore, approximately 4.
10 ¹⁸ molecules are required to cover 1 m ² of surface with a thin carpet of such molecules. The surface area required for a surfactant is approximately
It is ^25Å2 . When the hydrocarbon chains are branched or halogenated and when they contain, for example, aromatic rings, the required surface area is correspondingly increased. Given that the strongly hydrophilic end group of a surfactant has a larger volume than the hydrophobic portion of its molecule, the hydrophobic group determines the surface area occupied by the molecule. If the solubility of the molecule in the aqueous phase (and its solubility in the organic phase, if any) and the absorption density at the container wall are known, the number of surfactant molecules at the surface or interface of the aqueous phase can be determined accurately. can be determined in advance or adjusted experimentally. This is convenient when the solubility in the two phases and the absorption density at the container wall are zero. The surfactant is then dissolved in a readily volatile or water-soluble solvent or solvent mixture (eg ethanol or chloroform/methanol) and the resulting solution is carefully dropped onto the surface or interface. The solvent disappears in the bonding phase,
Surfactant remains on the surface or interface. Suitable raw materials for the process according to the invention include lipoids, those obtained therefrom, in particular the hydrophobic affinity of surfactants obtained from microbial membranes, in particular those of Thermoplasma acidophilum and Sulfolobus acidocaldarium. There are substances.
Under the best environmental conditions (optimum growth of microorganisms is PH2.0,
obtained at 59°C). The cell membrane of the microorganism Thermoplasma acidophilum exhibits extremely high mechanical stability and high physical and chemical resistance. This distinguishes it from all biofilms studied to date. The most important structural element of these membranes is the difunctional lipoid, which provides acid and temperature resistance. This lipoid spreads throughout the membrane and has the following structural characteristics: This lipoid (hereinafter referred to as DGTE) can be used as a raw material in the method of this invention. This is particularly advantageous as the basic unit of the membrane of the invention. The ether-like bond between the hydrophobic element and the polar head group provides high resistance to acids. Mechanical chain branching on double bonds in other lipoids of biological origin avoids the risk of oxidative chain degradation. Hydrophobic bands in the center of the molecule can be bonded to each other through covalent bonds. DGTE is a unit of variable number that forms the membrane skeleton in different quantitative proportions. Since the end of the molecule facing the interior of the cell has a free primary alcohol group as a configuration, the externally coordinated groups can have substituents of different size and polarity. The number of phospholipoids containing phosphoryl monoglycosyl residues is quantitatively large. In addition, some other anionic phospholipoids are also present in small amounts. Lipopolysaccharide, whose substituents consist of a linear polysaccharide containing a glycose segment and 24 mannose residues, is a raw material of particular interest for the process of this invention. In this case, glucose
It forms a bridge between DGTE and polymannose. Mannose residues can be cleaved from -Glu-Man-Man residues with oxygen. This triglycosyl diglycerol tetraether is relatively easy to separate. This material is of particular interest in the process of this invention because it spreads very well in water and can crosslink in the subphase. DGTE-containing lipoids constitute more than 40% of the total lipoid compartment of cells. This can be easily isolated and washed, so that large-scale cultivation and optimization of the process will yield adequate amounts of each lipoid fraction. Regarding recovery of lipoids from biological membranes and their properties, see Tomas A, Langworthy; Biochem.
Biophys. Acta (Amsterdam) 487 (1977), 37~
Reference is made to page 50. Next, this invention will be explained with examples. Example 1 Manufacture of a single molecule for overseparation by spreading and polymerizing a surfactant having a diacetylene group Formula: _CH3- ( _CH2 ) ₁₂ -C≡C-C≡C-
Hexacosa10,12− represented by (CH ₂ ) ₈ −COOH
A chloroform solution of diyn-1-acid (1 mg/ml solution) was spread on the surface of the water in the Langmiur tank. After evaporation of the solvent (5 minutes), the remaining monolayer film was compressed at 20°C to a pressure of 15 dynes/cm. This film was irradiated with ultraviolet light (254 nm) for 6 minutes to polymerize. By lowering the water level, the above film was coated with an anisotropic ultrafiltration membrane made of regenerated cellulose [manufactured by Sartorius,
It was placed on a porous support (special product). Example 2 Production of a monomolecular layer for hyperseparation by spreading and polymerizing a surfactant having an acrylic acid ester group and a surfactant having a methacrylic acid ester group Formula (I): Represented by [Formula] With 0.95 mg of the compound to be expressed, the formula (): 0.05 mg of the compound represented by was dissolved in 1 ml of chloroform. As in Example 1, this solution was spread on the water surface in the Langmiur tank at 20°C, chloroform was evaporated, and then compressed to a pressure of 20 dynes/cm. Next, in the same manner as in Example 1, this film was irradiated with ultraviolet light (254 nm) to polymerize. The film was placed on a cellulose triacetate anisotropic ultrafiltration membrane (Sartorius, SM14539) by lowering the water level. Example 3 Adhesion of a monomolecular layer for hyperseparation to a porous support In addition to the carboxylic acid used in Example 1, 5% by weight of the formula: CH ₃ (CH ₂ ) ₁₂ -C≡C-C≡C −
(CH ₂ ) ₈ −O−OP(OH) ₂ , [Pentacocer 9, 10
A chloroform solution similar to that in Example 1 was prepared, and the same operations as in Example 1 were performed, except for adding the monophosphoric acid ester of diyn-1-ol]. The obtained film was polymerized and placed on a regenerated cellulose anisotropic ultrafiltration membrane (special product manufactured by Sartorius) in the same manner as in Example 1. The membrane was then removed from the Langmiure tank and placed in a dryer for 1 hour.
Tempered at 30°C for an hour. This operation fixes the separation layer to the support. Example 4 Fixation of monomolecular layer for hyperseparation to porous support Compounds of formulas (I) and () were mixed with 1 ml of chloroform.
The same operation as in Example 2 was carried out except that 0.80 mg and 0.20 mg were dissolved respectively. The support membrane used was an anisotropic ultrafiltration membrane of cellulose diacetate treated with boiling ethylene sulfide (56° C.) steam (1 mole of ethylene sulfide per mole of free hydroxy groups). This monomolecular film was polymerized and placed on the support layer, and then the polymerized film was fixed to the support in the presence of gaseous trimethylamine at room temperature in a humid chamber. This method could be performed in a time not exceeding 15 minutes. Example 5 Preparation of a superseparation monolayer with a hydrophilic surface and fixation of the layer to a porous support Formula (): and a compound of the formula (): _CH3- ( _CH2 ) _12- C≡C-C≡C-
(CH ₂ ) ₈ -COOH compound in chloroform 1
A total amount of 1 mg per ml was dissolved in chloroform in a molar ratio of 1:1. The aqueous subphase in the Langmiur tank was adjusted to pH 8, the above solution was spread on the aqueous subphase in the Langmiur tank, the solvent was evaporated, and the resulting film was heated at 15 dynes/ Compressed to cm. An anisotropic ultrafiltration membrane of cellulose diacetate is then placed in the lower layer of the Langmiur tank at a constant spreading pressure.
At the bottom, the unpolymerized film was transferred onto the support membrane by lowering from above (dipping or stamping step). Here, the "spreading pressure" corresponds to the difference between the surface tension of the pure liquid (aqueous phase) surface and the surface tension of the liquid covered with surfactant molecules. This difference is due to the thermodynamic movement of the surfactant in two dimensions (similar to the movement of gas molecules in three dimensions in a container) of the surfactant before crosslinking, which spreads over the surface of the aqueous phase. Next, by irradiating the film with ultraviolet rays, the film was simultaneously polymerized and fixed to the support membrane. Example 6 Preparation of superseparation monolayers by cross-linking extended hydroxy-containing surfactants A solution of n-octadecylgluconamide (0.4 mg) in a mixture of 2 parts chloroform and 1 part methanol /ml) was prepared at 50°C. After spreading this solution in a Langmiur tank and evaporating the solvent,
It was compressed to 16 dynes/cm. The film was stable and was loaded onto a cellulose diacetate anisotropic ultrafiltration membrane by lowering the water level. The membrane was then fixed using gaseous epichlorohydrin in a humid chamber at 20° C. for 12 hours. According to this method, the monomolecular film is cross-linked and fixed to the support membrane. Example 7 Production of a monomolecular layer for superseparation by simultaneously spreading and crosslinking a surfactant having an amino group and a surfactant having a hydroxyl group Mixed solvent of chloroform: methyl alcohol (2:1) The same procedure as in Example 6 was carried out except that a solution containing 0.24 mg of octadecylamine and 0.40 mg of n-octadecylgluconamide per ml was used. The film obtained from this solution is
At 30 dynes/cm it was liquid. After this film was placed on an anisotropic limiting membrane of cellulose diacetate, the membrane was first prefixed with gaseous epichlorohydrin at 20°C for 70 hours, and then placed in a 1% hexamethylene diisocyanate solution in trichloroethylene. Fixation was completed by soaking for 10 minutes at room temperature. Example 8 Production of a superseparation monolayer with a negative surface charge by spreading and crosslinking a surfactant having a hydroxyl group Mixing of ω-bromo-octadecylgluconamide in chloroform/methanol (2:1) Initially, the procedure was the same as in Example 6 except that a solvent solution was used. After the film was placed on the ultrafiltration membrane, it was prefixed with gaseous epichlorohydrin and the fixation was completed with hexamethylene diisocyanate in the same manner as in the Examples. The entire membrane was then thoroughly washed with water, treated with a 5% NaSH aqueous solution for 30 minutes at 40°C, washed again, immersed in a 5% propane sultone solution in toluene for 10 minutes at 40°C, and finally washed once again with water. Example 9 Preparation of a superseparation monolayer with a polar and chiral surface A membrane was prepared in the same manner as in Example 8, except that the membrane was treated with dl-1-methylpropane sultone. Example 10 Production of a monomolecular membrane for hyperseparation by cross-linking a spread layer of surfactant and a gel layer of polyvinyl alcohol (PVA) A glass plate was coated with a monomolecular layer of Cd ²⁺ arachinate by a known method. to make it hydrophobic. The plate thus produced was transferred to an aqueous sublayer at a speed of 2.4 cm/sec through a monomolecular film of octadecyl gluconamide and octadecyl amine (see Example 7) spread at 30 dynes/cm. Completely immersed from the top. After removing the monomolecular film remaining on the liquid surface, the plate was taken out again. This plate is coated with different monomolecular films. The board was briefly dried and then immersed in a 20% PVA aqueous solution. After an additional 5 minutes, the board was removed from the PVA aqueous solution and hung from its top for an additional 5 minutes to drain any adhering liquid. It's still attached after that
The PVA solution was removed from the bottom edge of the board with paper and then the board was dried on silica gel in an oven. The plate was then introduced into a chamber filled with gaseous hexamethylene diisocyanate and left there for 15 minutes. The crosslinked PVA-surfactant layer was then removed from the glass plate and washed with water. Example 11 Production of hollow fibers with separating bilayer for gas separation Hexacosa 10, which was prepared by expanding porous polypropylene hollow fibers at 0° C. under a pressure of 20 dynes/cm.
Through a monomolecular film of 12-diyn-1-acid,
It was immersed at a speed of 2.4 cm/sec into an aqueous sublayer containing 1 g/CdCl ₂ . After complete immersion, the fibers were pulled up again under the same pressure, and the lowermost ends of the fibers were left in the lower layer for 5 minutes to remove the adhering lower layer liquid, and then completely taken out. After that, the liquid still adhering to the ends of the hollow fibers was removed with paper. The bimolecular film on the surface of the hollow fiber was then cross-linked for 1 minute by gently rotating the fiber in front of an ultraviolet aperture radiator (4000 mW/cm ² ). These examples are representative and do not limit the invention.

[Brief explanation of drawings]

FIG. 1 shows a cross section of a normal membrane, FIG. 2 shows a cross section of an example of the membrane of this invention, FIG. 3 shows a cross section of another example of the membrane of this invention, and FIG. 4 shows a cross section of another example of the membrane of this invention. Figures 5 to 8 are cross sections showing specific examples of the monomolecular film of the present invention, and Figures 9 to 11 are cross sections of the bimolecular film of the present invention, respectively. FIG. 3 is a diagram showing a cross section of another specific example of a separated separation layer. 1, 3...separation layer, 2...support layer, 4...gel layer.

Claims (1)

[Scope of Claims] 1. The separation layer is composed of molecules of a crosslinked monomolecular film, and (a) at least one molecule of the separation layer is in an uncrosslinked state.
(b) The hydrophobic chains of the cross-linked molecules are mainly arranged perpendicular to the membrane surface and parallel to the diffusion direction. (c) the molecules of the separating layer are crosslinked to each other via a functional group in at least one hydrophobic chain thereof and/or via a functional group in at least one hydrophilic group thereof; membrane containing a separation layer and a support layer. 2. A membrane according to claim 1, in which at least some molecules of the separation layer are also crosslinked via hydrophilic groups with molecules of the support layer. 3. The membrane according to claim 1, wherein all molecules of the separation layer are crosslinked with molecules of the support layer via hydrophilic groups so that molecules of the separation layer are crosslinked with molecules of the support layer. 4. A membrane according to any one of claims 1 to 3, wherein the separation layer and support layer of the membrane are bonded to each other via a gel layer, and the molecules of the separation layer are optionally fixed to the molecules of the gel layer. . 5. A membrane according to any of claims 1 to 4 in which at least some of the surface-active molecules have chiral centers. 6 The chiral center is a mono-, di-, tri- or higher saccharide residue, amino acid residue, oligopeptide residue, amino sugar residue, ionic acid (1- or 6-carboxyl-substituted sucrose) residue, sugar acid residue, ether 6. A membrane according to claim 5, wherein the sulfonate residues or derivatives of these substances are located. 7. A patent claim characterized in that carrier molecules, pore molecules, or molecules that form pores between molecules are dissolved or incorporated into a separation layer of a membrane consisting of a surfactant or a surfactant-like lipoid. A membrane according to any one of the ranges 1 to 6. 8 (a) Surfactant molecules or surfactant-like lipoid molecules are spread on the surface of the aqueous phase or at the interface between the aqueous phase and an immiscible liquid, maintaining a certain spreading pressure or average spacing, and ( b) crosslinking the surfactant molecules or surfactant-like lipoid molecules with each other; and (c) coating the separation layer thus crosslinked on a support membrane or gel layer, and carrying out these steps continuously. , but process (b) and process (c)
(1) The separation layer is made of a crosslinked monomolecular film, and (1) the molecules of the separation layer in an uncrosslinked state contain a surfactant or a surface containing at least one hydrophobic chain and at least one hydrophilic group. It is an activator-like lipoid, (2) the hydrophobic chains of the cross-linked molecules are mainly arranged perpendicular to the membrane plane and parallel to the diffusion direction, and (3) the molecules of the separation layer have at least one of its hydrophobic chains. A process for producing a membrane, characterized in that it obtains a membrane comprising a separating layer and a support layer, which are crosslinked to each other via functional groups in the chains and/or via functional groups of at least one hydrophilic group thereof. . 9 A supporting layer of a separation layer in which a crosslinkable gel is contained or a crosslinkable polymer is dissolved in the aqueous subphase or in the water-filled pores of the support layer, and the surfactant molecules are crosslinked or are crosslinked. 9. A method according to claim 8, comprising sequentially crosslinking the crosslinkable gel or polymer with surfactant molecules or with a crosslinked separation layer or with itself after application to the crosslinkable gel or polymer. 10. A method according to claim 8 or 9, comprising crosslinking the support layer before or after crosslinking at least some of the surfactant molecules or surfactant-like lipoid molecules. 11 After cross-linking of the separation layer molecules, either before or after coating the separation layer onto the gel layer or support layer and optionally after the various layers have been cross-linked to each other, the surfactant molecules separated from the support layer A method according to any one of claims 8 to 10, which comprises introducing a hydrophilic or hydrophobic group into the weakly hydrophilic end or converting it into a hydrophilic or hydrophobic group. 12. The method according to claim 11, which comprises introducing or converting an optically active hydrophilic group or hydrophobic group into a weakly hydrophilic end of a surfactant molecule remote from the support layer. 13 Claim 1 comprising reacting the weakly hydrophilic end of the surfactant molecule remote from the support layer with a sultone, optionally an optically active sultone.
Method according to Section 1 or 12. 14. Patents in which the surfactant or surfactant-like lipoid molecules are excipients or are extended with hydrophobic molecules that have internal pores or are associated with each other such that pores are formed between the molecules. A method according to any one of claims 8 to 10. 15. Spread the molecules at the surface of the aqueous solution or at the interface of the aqueous solution and an immiscible liquid while maintaining a certain spreading pressure or average spacing, and then introduce the hydrophobic plate into the aqueous phase through the surface or interface. immersion, whereby the monomolecular surfactant film is hydrophobically deposited onto the plate under constant spreading pressure, the remainder of the monomolecular surfactant film is then removed from the surface or interface by suction, and the plate is removed from the adhered monolayer. By sequentially removing the molecular film from the aqueous phase and then crosslinking the monomolecular film, the separation layer consists of molecules of the crosslinked monomolecular film, and (a) the separation layer in an uncrosslinked state is formed. has at least one molecule of
(b) The hydrophobic chains of the cross-linked molecules are mainly arranged perpendicular to the membrane surface and parallel to the diffusion direction. (c) the molecules of the separating layer are cross-linked to each other via a functional group in at least one hydrophobic chain thereof and/or via a functional group in at least one hydrophilic group thereof; A method for obtaining a membrane comprising a separation layer and a support layer. 16 Before or after crosslinking the monomolecular surfactant film, the plate is immersed together with the film in a crosslinkable polymer solution, removed from the solution, and after draining off the adhering liquid and optionally after drying, the crosslinkable polymer is crosslinked. 16. A method according to claim 15, comprising: 17. The method according to claim 16, wherein the crosslinkable polymer is polyvinyl alcohol. 18. The method according to claim 15, wherein the monomolecular film is coated on the support membrane after crosslinking. 19 Using hydrophobic hollow fibers with pore walls or bundles of such hollow fibers instead of hydrophobic plates,
19. A method according to any one of claims 15 to 18, which comprises leaving the monomolecular film on the surface of the hollow fiber after crosslinking, and optionally carrying out the coating and crosslinking a plurality of times. 20 Hydrophobic hollow fibers or bundles thereof with pore walls are first introduced into an aqueous phase, and then a monomolecular film is spread on the surface of the aqueous phase or at the interface between the aqueous phase and an immiscible liquid phase. Then, the hollow fiber or a bundle thereof is taken out from the phase interface under constant spreading and pressure so that the hollow fiber surface is hydrophilically crosslinked with the monomolecular film, and if necessary, this coating and crosslinking are performed multiple times. Method according to scope item 19.